Cook Islands Police Service spokesman Trevor Pitt said Taana John, aged 20, was last spotted on the Rarotonga Hospital road wearing black shorts and no shirt or shoes.
While John was not considered dangerous, he should not be approached, Pitt added.
“Police and prison staff are conducting a search. Please contact the police should you have any information on the whereabouts of this inmate.”
Pitt said prison staff had notified police of the escape at about 10am yesterday.